Reincarnated Into a Game as the Hero’s Friend: Running the Kingdom Behind the Scenes (Manga) Vol. 2

THE BATTLE’S NOT OVER YET!
Lord Werner’s saved the day! Well, almost. Having been reincarnated into a game he played when he was young, Werner brings his knowledge of upcoming events to change the tide of battle and survive against the dreaded Demon Stampede.
Meanwhile, the hero Mazel comes face to face with one of the Demon Lord’s trusted commanders. Werner knows his friend will succeed, but can this former office worker defy fate to save the lives of his troops?
Series Overview: A modern man is reincarnated into the world of a fantasy game he knows well: as Werner, the son of a powerful noble. The thing is, Werner isn’t the hero or even the villain–he’s a background character likely to die during a climactic siege!
Werner seeks out and befriends the hero, but he doesn’t have powerful enough skills to be a hero himself. Unwilling to die as a later plot point, Werner uses his knowledge of the game and his power as a noble to aid the hero and defend against evil attacks.
That’s when he realizes that when he does so, he saves other people who were doomed as he was, which changes the “plot” he thought was inevitable. As the hero’s close comrade who can see the future, perhaps Werner will be a savior to this place, after all!